Air conditioning units



Dec. 12, 1961 W. L. M GRATH AIR CONDITIONING UNITS Filed March 1, 1957 2 Sheets-$heet 1 FIG. 2

INVENTOR. WILLIAM L. McGRATH.

BY W (M ATTORNEY.

Dec. 12, 1961 w. MCGRATH 3,012,760

AIR CONDITIONING UNITS Filed March 1, 1957 2 Sheets-Sheet 2 BY W ATTORNEY.

nits- States 3,012,760 Patented Dec. 12, 1961 3,012,760 AIR CONDITIQNING UNITS William L. McGrath, Syracuse, N.Y., assignor to Carrier Corporation, Syracuse, N.Y., a corporation of Delaware Filed Mar. 1, 1957, Ser. No. 643,428 13 Claims. (Cl. 257-137) This invention relates to air conditioning units and more particularly to improved air conditioning units containing means to maintain a supply of primary air at esired conditions of pressure and to discharge the primary air within the unit in such a manner as to induce a stream of secondary air from the area being conditioned through a heat exchange member in the unit to mix with the stream of primary air, the mixture of primary and secondary air being discharged within the area being treated.

In Carrier Patent #2363194, granted November 21, 1944, there is disclosed an air conditioning system for rnulti-room buildings which contemplates a supply of conditioned air from a central station at high velocity and static pressure through small conduits to room units placed in the rooms being conditioned. Each room unit includes a heat exchanger through which cold or hot water may be passed, depending upon temperature conditions exteriorally of the building. Th stream of conditioned primary air (cold or warm) from the central station is discharged into the unit at a velocity such as to induce a secondary stream of air into the unit through the heat exchanger to mix therewith. The mixture of streams is then discharged into the room to cool or heat the same.

The system outlined by the Carrier patent has been acknowledged by the air conditioning industry to present an ideal method of air conditioning from the standpoint of operation, maintenance and economy. Owners of buildings, however, have demanded that these units be made especially compact since the space so conditioned is rented on the basis of square foot area. A bulky unit will severely decrease the rental value of a space being so conditioned.

The problem of making a more compact unit has been aggravated by the widespread use of glass on the exterior of the building. The architect of the building by making extensive use of glass in designing the building, has greatly decreased the insulation qualities of the building and simultaneously increased the air conditioning load thereon, thereby forcing the use of air conditioning units of greater capacity to compensate for this increase in load. Furthermore, in designing a building with greater outside glass area, the windows have come closer to the floor level, thereby severely restricting the amount of space allotted for the induction unit. In making units of a more compact character, a further problem is encountered in that the noise levels attained by these units very often becomes very unpleasant to the tenants or guests.

The chief object of the present invention is to provide an improved high capacity induction unit.

An object of the invention is to provide an improved air conditioning unit capable of making effective use of a limited amount of heat exchange surface.

Another object is to provide an improved air conditioning unit utilizing improved induction nozzles.

A still further object is to provide an air conditioning unit capable of harmonizing with the esthetic qualities of the building without sacrificing capacity. jects of the invention would be more readily perceived from the following description.

This invention relates to an air conditioning unit which comprises in combination a casing including a plenum Cir Other obtherein, said plenum being connected to a source of primary air, air discharge means connected to said plenum, a heat exchange member adapted to be connected to a source of supply of heat exchange medium, said air discharge means comprising a plurality of nozzle members arranged to discharge a swirling helical airstream of expanding diameter adapted to induce a secondary air stream from the area being conditioned through the heat exchange member into heat exchange relation with medium passing therethrough to mix with the primary air being discharged from the plenum through the discharge means and means for discharging a mixture of primary air and secondary air within the area being conditioned.

The attached drawings illustrate a preferred embodiment of my invention, in which:

FIGURE 1 is a perspective view of the air conditioning unit of the present invention installed in a room being conditioned;

FIGURE 2 is a sectional view of the unit;

FIGURE 3 is a sectional view of the unit with the heat exchange member removed;

FIGURE 4 is a plan view of the unit;

FIGURE 5 is a perspective view of the simplified air discharge means for use in the unit;

FIGURE 6 is a plan view similar to FIGURE 4 illustrating a modification of the invention; and

FIGURE 7 is a further modification of the invention as illustrated in FIGURE 6 Referring to the attached drawings there is shown in FIGURE 1 an air conditioning unit placed beneath the window of a room being treated. This air conditioning unit includes a casing 2 which is provided with two air discharge openings 4 and a series of louvered air inlets 3 on the side of the casing. Air conditioning units of this type are placed beneath most of the windows in the building in such a manner so as to provide a peripheral blanket of air about the building. It will be immediately appreciated that in buildings, such as office buildings, hotels, et cetera, the number of units employed may easily exceed a thousand. It will be appreciated in certain instances the unit may be externally located, such as illustrated in FIGURE 1 or the unit itself may be furred into the wall so as to harmonize with the surroundings.

Referring to FIGURE 2, there is shown a sectional view of the unit wherein the section is taken in a plane normal to the front of the unit, the afore-mentioned louvered openings 3 and 4 are shown and at the lower part of the unit there is indicated a plenum 5 which is preferably lined with an insulating material 7. Leading into this unit is a circular conduit 6, which is connected to the central station of the air conditioning system and is utilized to supply high pressure primary air to the plenum 5. Located in this plenum is a bafile 8. It is apparent that other arrangements of battles and sound absorbing means may be utilized within this plenum while still remaining within the scope of the present invention. A heat exchange member is located above the plenum 5. This heat exchange member 10 is of the plate fin type and is made up of a plurality of parallel spaced trapezoidal fin members 11 attached to tubes 12. These tubes 12 are interconnected by suitable return bends so as to form a circuit through which heat exchange medium is circulated. These fins, as mentioned, are of a trapezoidal shape with the lower portion of the plate being of a greater width so as to have a greater surface area at the lower portion thereof, this area decreases as the distance from the plenum increases. The purpose of this construction will be described more fully hereinafter.

, Located adjacent the heat exchange member 10 are nozzle means'9 which consist of a plurality of nozzles arranged in clusters, each cluster having. a substantially circular pattern, the nature of which will be described more fully hereinafter. The nozzles are located in the upper wall of the plenum and are adapted to discharge the air supplied to plenum 5 into the air conditioning unit in such a manner as to induce a secondary air stream through the inlet 3 and the heat exchange member 16.

Located above the nozzle cluster 9 are side baffles 13 and 13 which are utilized to maintain the contour of the helical air streams within the air conditioning unit. Located beneath the outlet 4 of the air conditioning unit is a bafiie 14 which directs the air stream emitted from the air conditioning unit away from the window. The manner in which this is accomplished will also be described more fully hereinafter.

Referring to FIGURE 3 there is shown a view in elevation of the unit with the heat exchange member removed so as to view the internal sections of the air conditioning unit. It will be noted that air is supplied through a spiral conduit 6 which extends into one side of the air conditioning unit. FIGURE 3 shows an embodiment of the unit employing four nozzle clusters 9, 9, and 20'. It will also be noted that the nozzle clusters are located in pairs, namely, 9 and 9, and 2t and 20. The clusters 9 and 9 cooperate and they discharge into confined paths to the specific outlet 4 restrained by the bafiles 13 and 13'.

A front view of the baffle 14 is shown and it is indicated as a plate which interrupts the flow of the tapered helical air streams emerging from the nozzle cluster 9. The object of such a bafile is to prevent the flow of air toward the window of the room by acting as a deflector so as to direct the air in a screen passing upwardly in front of the Window and into the room. Located adjacent the first pair of nozzle clusters is a second set of nozzle clusters 20 and 20, which are confined to their specific paths by the side baffies 22 and 22 which is an equivalent structure to that shown previously with a bafile 21 whose function is similar to the bafiie 14.

FIGURE 4 illustrates a plan view of the unit previously shown in FIGURES 2 and 3. From this view it is readily apparent that nozzle clusters 9, 9, 20 and 20 each comprises a center nozzle with a plurality of other nozzle members dispersed in a general circular pattern about the central nozzle member. The location of the baffle plates 14 and 21 are shown and it is clear at this point that as the air emerges through the opening it will be restrained from passing toward the outer wall or window of the building by means of these bafi le plates which direct the air impinging thereon in a vertical air stream into the room. FIGURE 4 also indicates the heat exchange member 10 with its return bend 28 and its cooling medium inlet and outlet 26.

Referring to FIGURE 5 there is shown a simplified nozzle construction 9. The nozzle construction consists of five nozzle members. A center nozzle member is attached to the plate 29 which comprises the upper portion of the plenum 5. About the center nozzle 30 are placed a plurality of nozzle members 31, 32, 33 and 34. The nozzle members in this particular embodiment lie in a concentric circle about the nozzle 30. Nozzle members 31, 32, 33 and 34 are directed in a direction tangential to a circle drawn through the afore-mentioned nozzle members concentric with the nozzle 30. The nozzle 30 is directed in a direction normal to the plane of the member 29. Nozzles 31, 32, 33 and 34 are arranged in an acute angle with respect to the plate 29. However, the projection of the direction of air flow therefrom will be as previously mentioned tangential to a circle concentric with the center nozzle 30. By this construction a swirling air flow is created in such a manner so that an expanding tapered helical air path is defined. This helical air path is further determined by back member 29 and the side baffles 13, 13', 22 and 22' of the unit. By this construction the linear air flow path of the air emitted by the nozzles is considerably lengthened because of the helical path. In this manner a more effective induction of secondary air is assured from the room through the heat exchange member and out through outlet 4.

Referring to FIGURE 6 there is shown a modification of a nozzle cluster orientation of the invention as previously illustrated in FIGURE 4. As in the previous em bodiment the heat exchange member 10 is located in the forward section of the unit and may be of a similar cross section and plate size as the heat exchange member 10 shown in FIGURE 2. However, in orienting the nozzle clusters in this particular embodiment instead of utilizing side baffles, the various nozzle clusters are equally distant along the entire length of the unit with the alternate nozzle sections orientated in different directions so that a staggered line of clockwise and counter-clockwise rotating air streams are emitted by the various nozzles 40, 41, 42 and 43.

Another embodiment of the invention is illustrated in FIGURE 7. As will be noted from the previous embodiments, the entire plan of such a nozzle cluster and unit construction is to maintain the longest lineal length of air stream possible in front of the heat exchange member so that a greater amount of secondary air may be induced from the room being conditioned. Furthermore, this particular construction makes it possible for the backmost nozzle members of each cluster to contribute to the induction effect. In order to lengthen the air stream, the embodiment of FIGURE 7 has a nozzle mounting plate oriented in such a manner so that the plane of each cluster is disposed at an angle to a horizontal plane as viewed through the section taken in a plane parallel to the front of the unit.

Primary air enters the embodiment shown in FIGURE 7 through a conduit extending into the plenum 51. The plenum is provided with two sets of nozzle clusters 55 and 56 which pass through the upper wall thereof. The nozzle clusters 55 have a projection toward the left whereas the nozzle clusters 56 have a projection toward the right. Nozzle clusters 55 pass air therefrom in a plurality of tapered helical paths toward the outlet 52. The paths are determined by the heat exchange member 10 (not shown) the back plate of the unit and the side bafiles 57 and 58. A similar arrangement occurs on the right side of the unit wherein the clusters 56 pass air through the outlet 53 and the tapered helical paths are determined by the backplate of the unit and the side baffies 59 and 60. By this particular arrangement a convenient space for a control center 54 is provided between the openings 52 and 53.

In operation, a central station (not shown) supplies conditioned air to the duct 6 (FIGURE 3), and into the plenum S. Simultaneously the central station provides heating or cooling medium for the heat exchange member 10. Referring to FIGURE 2, air from the duct 6 passes into the plenum 5 where the movement of air is sufficiently mufiled by the insulating material 7 which lines the plenum. The air is then discharged upwardly through the nozzle clusters 9 and in the form of swirling air streams which are constrained by the back member 29 of the unit, the heat exchange member 10, the side bafiles in the unit and adjoining air streams. The location of the side walls and the heat exchanger are such that an expanding opening is provided which in effect restrains and determines the particular shape of the air stream. As the mass of swirling air reaches the vicinity of the opening 5, it is partially constrained by the bafiles 13 and 13' which direct the air up through the louvered opening 4. Because of the rotating nature of the air, a component of the air stream may, if not restrained, pass toward the window. For this purpose the baffle 14 is provided which deflects this component of air in such a manner so that this component joins the great mass of air passing through the opening 4 and forms a vertical screen before the window and then passes into the room.

The helical pattern within the unit insures a high degree of induction of secondary air and also makes full use of the depth of the unit by bringing all the nozzles therein into direct cooperation in such a manner so that the rear section of the unit is effectively utilized. It is well known that the amount of induction of secondary air is proportional to the length of the air stream within the confines of the unit. The helical air stream is one of the methods of the present invention to achieve this lengthened air stream.

In order to emphasize the heat exchange process within the unit, a heat exchanger of varying air resistance is used to take advantage of the greater inductive effect of the primary air adjacent the nozzles. The heat exchanger used herein is of the plate fin type having a trapezoidal plate construction wherein the lower portion of the plates have a substantially greater surface area than the upper portion thereof. By this type of construction the greater inductive effect of the air stream in the vicinity of the nozzle is advantageously utilized since the passage to the lower section of the heat exchanger provides a greater resistance to air passing therethrough because of the greater length of the constructed passage. As the distance from the nozzle clusters increases this resistance through the heat exchanger is decreased. This results in a uniform passage of air through the heat exchanger because the velocity of the air streams issuing from the various nozzles are substantially greater at the nozzles and therefore at that point they have greater inductive ability. As the distance from the nozzle cluster increases, the reduced inductive effect of the air stream is compensated by the decrease in resistance to air flow through the upper portion of the heat exchange member 10.

Referring to FIGURE 3, there is shown an arrangement wherein the nozzle clusters are utilized in pairs so that the rotation of the air streams in a particular pair is in opposing relationship. By the arrangement of this particular embodiment, the adjoining air streams will assist one another and thereby produce a substantial increase in the induction rate. Furthermore, the adjoining air streams will act as buffers toward one another and thereby insure that a substantial vortex is formed in each cluster throughout the entire depth of the tapered helical air stream.

FIGURE as previously mentioned discloses an elemental nozzle cluster construction utilizing four nozzle members. As it will be recalled a center nozzle is provided whereabout are located four nozzles on a circle concentric with the center nozzle. The direction of the nozzles have a projection which is tangential to the circle so drawn. These peripheral nozzles are also directed at an angle from the plane of the nozzle plate 29. The center nozzle will form a direct upward component of an air stream whereas the external nozzles will form a swirling mass of air constrained through a particular conical path by the environment within the unit which includes the back walls, the various battles, and the heat exchange member. By this particular nozzle orientation a substantial air flow is created within the area between the heat exchange member and the back wall 29 of the unit. By utilizing the entire depth of the unit and as a result of the tremendous mass of air passing through the unit, a great induction rate may be had through the heat exchange member 10, plus the fact that the trapezoidal plate members will create a more efiicient and effective heat exchange process.

FIGURE 6 discloses a modification whose operation is similar to that of FIGURE 4, however, in this particular embodiment, the nozzles are spaced equally and instead of using side baflles, the air streams impinge in such a manner so that to form buffers and duplicate the baffle action of the previous embodiment. This particular construction therefore permits the use of a greater number of nozzle clusters and makes greater use of a given amount of space within a particular air conditioning unit.

FIGURE 7 illustrates a modification of FIGURE 6 in which the particular nozzle clusters are placed at an angle so that the helical paths issuing therefrom do not have their vortices extending vertically but rather at an angle to a horizontal plane. This particular embodiment especially emphasizes the concentrated induction process which can be carried out in a unit of limited height. By having the various helical tapered air paths inclined at an angle, a longer helical path of air may pass before a heat exchange member of limited height. This construction especially lends itself to new structures wherein the entire wall is substantially made of glass with merely a slight parapet running along the periphery of the wall above the floor level. It will also be evident that this particular embodiment does not require the particular nozzle cluster illustrated in FIGURE 5 since the length of the primary air streams are considerably longer than the minimum distance from the nozzles to the outlet.

The air conditioning units of the present invention present extremely compact and elfective induction units especially adapted for modern buildings wherein the space available for these units is extremely limited. It will be noted that this particular result is achieved by a highly novel and effective heat exchange member combined with a novel form of nozzle cluster which is adapted to increase the effective heat exchange potential of the heat exchange member.

While I have described the preferred embodiment of the invention it will be understood that the invention is not limited thereto since it may be otherwise embodied within the scope of the following claims.

I claim:

1. In an air conditioning unit, the combination of a casing, means defining an inlet to said casing, means de fining an outlet from said casing, a plenum located within said casing, said plenum being connected to a supply of primary air and nozzle means associated with said plenum, comprising a cluster of nozzles oriented in a general circular configuration adapted to discharge primary air to form a swirling primary air stream having the general shape of a helix of expanding diameter, said nozzles being formed in a wall of the plenum, the discharge of primary air from the nozzles inducing a stream of secondary air from said room through said inlet to mix with said primary air, the mixture being discharged through said outlet.

2. The unit according to claim 1, in which a heat exchange member is placed within said unit adjacent the inlet so that the nozzle means induce the secondary air stream through the heat exchange member so that the secondary air is placed into heat exchange relation with medium passed through said heat exchange member.

3. The unit according to claim 1 in which the nozzles are oriented so that their openings point in a direction whereby the projection of the air streams onto the plane of the circle are substantially tangential with respect to the circle upon which said nozzles are oriented.

4. The unit according to claim 3 in which at least a pair of spaced nozzle clus ers are provided and the nozzle clusters have their individual nozzles directed so as to form clockwise and counterclockwise rotating air streams.

5. The unit according to claim 4 in which the nozzle clusters are spaced in parallel groups and in which their center axes are inclined to the horizontal plane.

6. In an air conditioning unit, the combination of a casing having means defining an inlet and an outlet, a plenum located at the lower portion of the casing and adapted to receive primary air, a heat exchange member disposed adjacent said inlet, a plurality of nozzle clusters being linearly disposed in a wall of said plenum, each cluster including a circular orientation of nozzles to form a swirling air stream having the general form of a helix of expanding diameter, means located within said casing to confine said air streams whereby the primary air stream induces secondary air to pass through the inlet of the casing and into heat exchange relation with medium p ssing thr ugh said heat exchange member and to mix with said primary air stream whereby said swirling streams a of primary and secondary air are discharged through said outlet.

7. The unit according to claim 6 in which the heat exchange member includes a plurality of vertically disposed parallel fins having a general trapezoidal shape, the greater area of the fins being located adjacent the nozzle cluster and said area diminishing as the distance from the cluster is increased so as to compensate for the diminishing inductive effect of the nozzle cluster whereby the secondary air stream passes through the heat exchange member in a substantially uniform pattern.

8. The unit according to claim 7 in which the clusters are spaced in pairs with each cluster forming a rotating air stream, the air streams rotating in ditferent directions.

9. The unit according to claim 7 in which the clusters are mounted so as to have their axes parallel.

10. The unit according to claim 7 in which the clusters are linearly disposed at equal distances.

11. The unit according to claim 7 in which the clusters consist of groups wherein all the clusters therein have their axes parallel and said axes are angularly disposed with respect to a horizontal plane.

12. In an air conditioning unit the combination of a casing, means defining an inlet to said casing, means defining an outlet from said casing, a plenum located within said casing, said plenum being connected to a supply of primary air, a heat exchange member placed in said casing adjacent said inlet, said heat exchange member having a varying resistance across the face thereof to air passing therethrough, and means for discharging primary air from said plenum into the casing to induce a stream of secondary air through the inlet into the heat exchange member into heat exchange relation with medium passing therethrough, said passage of secondary air being uniform through said heat exchange member, said discharge means being placed within the casing to discharge the primary air in a path of flow between the discharge means and the outlet of a length substantially greater than the minimum distance between the discharge means and the outlet whereby the volume of secondary air uniformly induced through said heat exchange member is substantially proportional to the length of the air stream formed by the discharge means within the unit, said stream of primary air mixing with said secondary air, the mixture being discharged through said outlet, the primary air discharging means comprising nozzle means located in pairs which cause portions of the primary air stream to swirl in opposite directions whereby said portions of the primary air stream cooperate in a manner to increase the inductive effect of the nozzle means.

13. The unit according to claim 12 in which the casing includes means to deflect the swirling air streams within said casing so as to maintain a helical configuration of expanding diameter.

References Cited in the file of this patent UNITED STATES PATENTS 1,291,632 Pease Ian. 14, 1919 2,140,305 Ashley Dec. 13, 1938 2,186,804 Hamilton Jan. 9, 1940 2,492,757 Meek Dec. 27, 1949 2,567,758 Ashley Sept. 11, 1951 2,607,193 Berggren et a1 Aug. 19, 1952 2,783,979 Blum Mar. 5, 1957 2,913,227 Bottorf et al Nov. 17, 1959 FOREIGN PATENTS 315,528 Switzerland Oct. 15, 1956 

